It has been called the vehicle of the future and the ultimate way to beat the rush hour commute.

It is the M 200G, otherwise known as a "flying saucer", which is being built by a company in Davis, California called Moller International.

It says the futuristic contraption will go on sale in a few months and hopes to expand production to 250 a year.

Company representatives say it is easy to operate, with plenty of leg room and space for a passenger.

But customers may still have a while to wait.

So far, the flying car's inventor has been hard at work for more than four decades - and despite frequent assurances that success is just around the corner, the vehicle has yet to get anywhere near the mass market.

'Highway in the sky'

Capable of vertical take-off and landing, the craft - so far a one-off prototype - hovers like a helicopter up to 10ft off the ground. Any higher and the driver would need a pilot's licence.

It is the brainchild of Dr Paul Moller, an aeronautics engineer who envisions a "highway in the sky" which he believes could cut conventional commuter traffic in half.

"Look at the sky above us - how many aircraft do you see? It's a great space that is not being utilised. That is what we plan to use. Cars are finished as a means of getting around. It's only a matter of time."

The flying saucer is powered by eight engines which can run on petrol, diesel or even ethanol.

Dr Moller and his team say they have already conducted more than 200 test flights and say the flying saucer could prove useful to rescue teams as well as landowners.

Faster versions

Moller International has yet to establish which US agency - the Federal Aviation Administration or the Department of Transport - will authorise its use.

It sees the flying saucer as a precursor to the M400 - otherwise known as the "Skycar" - which looks a bit like the Batmobile, also boasts vertical take-off and landing, and can be driven on the road as well as flown through the sky.

The company is currently offering an M400 for sale on its website at between $500,000 and $1m, depending on how many orders it receives.

Dr Moller says the Skycar could be in production within six years or so, and promises a vehicle capable of climbing 6,000ft a minute and travelling at up to 400 miles an hour.

Many promises

But the promise has been made several times before.

In 2003, the US financial watchdog, the Securities and Exchange Commission, filed a case against Dr Moller alleging that he had used "false and misleading statements" when trying to find fresh investors.

One example contained in court documents claimed that in 1997 his company's promotional material had predicted 10,000 sales of a 400-mile-an-hour flying car by 2002, and had promised a stock market listing - and a sharp rise in share prices - which never materialised.

The case was later settled out of court, with the company paying a civil penalty of $50,000.

So If Dr Moller and his magnificent men get their way, the days of dropping in to the shops or the office may not be far away.

But eager amateur aviators may be well-advised not to hold their breath.